1. Field of the Invention
The present invention relates to a network electronic component, a semiconductor device incorporating network electronic component, and methods of manufacturing them.
2. Description of the Related Art
There are network electronic components each of which has a plurality of resistive elements or dielectrics integrated on a single insulating substrate to constitute a composite circuit network. Although simple successive formation of resistive elements or dielectrics without forming a circuit network may be called an electronic component array, the term “network electronic component” is used in the specification to include such an electronic component array. Unexamined Japanese Patent Application KOKAI Publication No. 2000-348914 describes one example of such a network electronic component. The network electronic component described in the publication has a plurality of grooves provided on both sides of a ceramic substrate, and plural pairs of upper electrodes provided on the top side of the ceramic substrate at those portions which do not correspond to the grooves. Plural pairs of lower electrodes are provided on the bottom side of the ceramic substrate at those portions which do not correspond to the grooves, and plural pairs of side electrodes are provided on both sides of the ceramic substrate at those portions which do not correspond to the grooves. A thin-film resistor is provided between each pair of upper electrodes, and a protection glass layer, an intermediate glass layer and a coating glass layer are provided on a ceramic substrate including the thin-film resistor, etc. Nickel or solder is plated on the top surface of the electrode portion which comprises the upper electrode, the lower electrode and the side electrode exposed in that state.
In manufacturing the network electronic component with the structure, first, first break grooves and second break grooves are formed in a lattice pattern on the top side of an aggregate ceramic substrate having an area large enough to form a plurality of completed network electronic components, and through holes for the formation of side grooves are formed in the aggregate ceramic substrate on the first brake grooves. Next, an electrode paste is printed on the top side of the aggregate ceramic substrate to form upper electrodes, and an electrode paste is printed on the bottom side of the aggregate ceramic substrate to form lower electrodes. A resistor paste is printed between a pair of upper electrodes to form a thin-film resistor, a protection glass layer for protecting the thin-film resistor is formed by printing, and an intermediate glass layer and a coating glass layer are formed by printing. The aggregate ceramic substrate is diced along the first brake grooves to split the ceramic substrate into a plurality of unit ceramic substrates. Then, nickel or solder is plated on the top surface of the electrode portion which comprises the upper electrode, the lower electrode and the side electrode of each unit ceramic substrate.
According to the network electronic component with the structure, however, as the electrode portion comprises upper electrodes provided on the top side of the ceramic substrate at those portions which do not correspond to the grooves, lower electrodes provided on the bottom side of the ceramic substrate at those portions which do not correspond to the grooves, and side electrodes provided on both sides of the ceramic substrate at those portions which do not correspond to the grooves, the structure is complex. In addition, the manufacturing process involves a significant large number of steps and is thus troublesome. For example, the manufacturing process comprises a first brake groove and second break groove forming step, a through hole forming step, an upper electrode forming step, a lower electrode forming step, a thin-film resistor forming step, a protection glass layer forming step, an intermediate glass layer and coating glass layer forming step, a first brake groove dicing step, a side electrode forming step, a second brake groove dicing step, and a nickel plating and solder plating step. What is more, the side electrode forming step follows the first brake groove dicing step, and the nickel plating and solder plating step follows the second brake groove dicing step, thus making the manufacturing process extremely complicated.